Printing device with selecting mechanism employing a group of eccentrics



T. GASSINO ETAL PRINTING DEVICE WITH SELECTING MECHANISM EMPLOYING Oct.8, 1968 A GROUP OF ECCENTRICS SSheets-Sheet 1 Filed Feb. 17, 1967INVENTORS TERESIOYGAS o ILAFHO BOV BY 7%;ufi wfm GENT Oct. 8, 1968 T.GASSINO ETAL PRINTING DEVICE WITH SELECTING MECHANISM EMPLOYING A GROUPOF ECCENTRICS 3 Sheets-Sheet 2 Filed Feb. 17, 1967 ENTORS TERESIOGASSINO l RIO BOVIO :GENT

GASSINO ETAL 3,404,765 PRINTING DEVICE WITH SELECTING MECHANISMEMiLOYING Oct. 8, 1968 A GROUP OF ECCENTRICS Y 5 Sheets-Sheet 5 FiledFeb. 17, 1967 United States Patent PRINTING DEVICE WITH SELECTING MECHA-NISM EMPLOYING A GROUP OF ECCENTRICS Teresio Gassino and Ilario Bovio,Ivrea, Italy, assignors to lug. C; Olivetti & C'.', S.p.A., Ivrea,Italy, acorporation of Italy Filed'Feb. 17, 1967, Ser. No. 616,993

' Claims priority, application Italy, June 25, 1966,

17 Claims. (Cl. 197-55) ABSTRACT OF THE DISCLOSURE -l A printing devicecomprises at least a typecarrier provided with a plurality of differenttypes adapted to be selectively positioned by a motion aggregatingmechanism formed of a group of eccentrics, each one associated with acode unit and adapted to selectively assume one of two diametricallyopposite positions, at least an outer eccentric being rotatably mountedon an inner eccentric of said group.-The eccentrics are associated witha group of coaxialsimilar driven pinions selectively driven by a groupof coaxial similar driving pinions, connecting means being provided forenabling each one of said eccentrics to be bodily .rotated by theassociated driven pinion.

Background of the invention The present invention relates to a printingdevice for typewriters, teleprinters, accounting and like machines,having at least a typecarrier provided with a plurality of differenttypes, a motion aggregating mechanism for selectively positioning saidtypecarrier according to a predetermined code combination, saidmechanism comprising a group of eccentrics, each one associated with acode unit and adapted to selectively assume one of two diametricallyopposite positions, at least an outer eccentric being rotatably mountedon an inner eccentric of said group.

-It is known .a printing device substantially of the abovementioned'type, wherein each eccentric is integral with a pinion. Sinceduring the rotation of each inner eccentric the .outer eccentrics aredisplaced according to a circular -path,.the pinions are displacedbodily with said eccentrics.

Therefore, to rotate each pinion it is necessary to use a rack capableto rock so as to follow the above mentioned displacement of theeccentrics and pinions. This device has the disadvantage of requiringspecific means for guiding and operating the different racks.

Summary of the invention I The primary object of the invention is toobviate this disadvantage. According to the invention, in a printing de-'vi ce of the above type, I now provide a group of coaxial similardriven pinions associated with said eccentrics, a

i Brief descripgim 0f the drawings FIG. 1 is :a partial perspective viewof a printing device according to the invention taken from the front andleft side of the machine;

:FIG. 2-is another partial perspective view of the device of FIG. 1;

FIG. 31is a third partialperspective viewof the device of FIG. 1; l FIG.4 is a perspective view of a detail of thedevice taken from the rear andleftside of the machine. Description of the preferred embodiments oftheinvention With reference to the FIG. 1, the numeral 11 indicates aconventional paper platen, which is transversely stationary on themachine. The printing device comprises a set of four typewheels 12, eachone provided with sixteen types and rotatable on an individual pivot 13parallel to the platen 11 and secured to a corresponding plate 14. Eachplate 14 '(FIG. 3) is provided with -a pair of rectangular slots 15longitudinally slidable on a pair of hollow square bars 16 and laterallyguided by corresponding projections 17 of the bars 16. The two bars 16are secured to a pair of flanks 18 and 19 which together with the bars16 form a support of the wheels 12.

Furthermore, the printing device comprises a carriage genericallyindicated by the numeral 20 (FIG. 1), which is transversely movable stepby step rightwards with respect to the platen 11 in a manner known perse. Particularly, the carriage 20 comprises a pair of flanks 21 and 22secured to a pair of transverse shafts 23 (FIG. 3), slidably mountingthe bars 16, whereby the wheels 12 are adapted to be axially displacedwith respect to the carriage 20.

Each wheel 12 is integral with a pinion 24 (FIG. 4) engaging acorresponding rack 26, which is provided with a bent lug 27 by means ofwhich it is guided into a recess 28 (FIG. 3) of the plate 14. A bent lug29 of the plate 14 prevents the rack 26 from disengaging the pinion 24.Each rack 26 is also provided with a slot 30 (FIG. 2) engaging auniversal bar 31 secured to a bail 32 fulcrumed on a shaft 33 secured tothe flanks 21 and 22 of the carriage 20.

Furthermore, the printing device comprises a first motion aggregatingmechanism adapted to angularly position the wheels 12, and av secondmotion aggregating mechanism adapted to transversely displace the wheel12, said two code combination. Particularly the first mechanismcomprises a group of four eccentrics 35, 36, 37 and 38 having aneccentricity proportional to the powers of two, that is respectivelyproportional to 1, 2, 4, and 8 respectively. The eccentric 35 isintegral with a shaft 39 rotatably mounted on the flank 21 and on asleeve 40 secured to an intermediate plate 50 of the carriage 20. Eachone of the other eccentrics 36, 37 and 38 of the group is rotatablymounted on the eccentric having the next lower eccentricity. In turn thelargest eccentric 38 is embraced by the head of a connecting rod 41,which is provided with a pin 42 engaging a slot of the bail 32.

Each eccentric 35, 36, 37 and 38 is adapted to assume one of twodiametrically opposite positions under the action of a correspondingselection clutch generically indicated by 43. The clutches 43 are of thetype having mutilated gears and adapted to be synchronously engaged,substantially similar to the clutch described in the United StatesPatent No. 3,260,128 to T. Gassino et al. Particularly each clutch 43comprises a driven part 45, 46, 47 and 48 respectively, associated withthe eccentrics'35, 36, 37 and 38. Each driven part is formed of a drivenpinion 4'9 having two diametrically opposite portions 51 deprived ofteeth. The pinion 49 is secured to a hub 52 coaxial with the shaft 39and having a pair of additional teeth 54 and 56 axially mutually offset,but angularly aligned with the portions 51.

The driven part 45 is directly secured to the shaft 39. The driven part46 is secured to a sleeve 57 'rotatably mounted on the shaft 39. Aflange 58 secured to the sleeve 57 is provided with a radial notch 59engaged by a pin I -3 5 i 60 secured to the eccentric tatable with thedriven part 46. The driven part 47 is rotatably mounted on the sleeve 57and is secured to an arm 61 having a notch 62 engaged by' a pin 63 secured to the eccentric 37, which then results bodily rotatable with thedriven part 47. Finally, the driven part 48.i s idle on the shaft 39 andis secured to an arm 6.4 having a notch 65 engaged by a pin 66 securedto the eccentric 38, which then results bodily rotatable with the drivenpart 48.

Furthermore, each clutch 43 comprises a driving part 67, three of whichare rotatably and slidably mounted on a shaft 68 secured to the flank 22and to the plate 50 (FIG. 3) of the carriage 20, while the fourth one isrotatably and slidably mounted on asecond shaft 75 se-, curedto theflank 21 and aligned with the shaft 68. Each driving part 67 comprises apinion 69 meshing with a corresponding pinion 70 having a width largerthan the pinion 69, but substantially equal to the width of the pinion49. The pinions 70 are secured to a common sleeve 71 extended betweenthe flanks 21 and 22 and bodily rotatable but axially slidable on afluted shaft 72 rotatably mounted on the stationary machine frame andextended along the whole width of the machine. The shaft 72 iscontinuously rotated counterclockwise by a conventional electric motorof the machine through a belt 73 and a pulley 74 secured to the shaft72.

Furthermore, each driving part 67 comprises a pair of further teeth 76,only one of which is shown in FIG. 2, said teeth 76 being adapted toengage the additional teeth 54 and 56 to start the rotation of thecorresponding driven part 45, 46, 47 and 48. The teeth 76 of each part67 are diametrally opposite, but axially mutually aligned. Furthermore,the teeth 76 of the different parts 67 are located at the same angularposition whereby the different driven parts 45, 46, 47 and 48 may besimultaneously started, that is the clutches 43 are synchronouslyoperated. Each driven part 45, 46, 47 and 48 normally faces thecorresponding driving part 67 with one of the portions 51 and with theadditional tooth 54 or 56 which is out of the plan of the teeth 76.

The second motion aggregating mechanism comprises a group of twoeccentrics 77 and 78 (FIG. 3) having an eccentricity according to theratio 1:2. The eccentric 77 is integral with a shaft 79 rotatable on theflank 22 and on the sleeve 40. The eccentric 78 is rotatable on theeccentric 77 and is embraced by the head of a connecting rod 81. Thislatter is provided with two lugs 82 engaging a pin 83 of a bail 84fulcrumed on a longitudinal shaft 86 secured to the carriage 20. Anotherpin 87 of the bail 84 engages a notch 88 of a projection 89 of the flank19.

Each eccentric 77 and 78 is adapted to be rotated 180 degrees under theaction of a corresponding clutch 91 similar to the clutches 43 andcomprising a driven part 92, respectively 93, similar to the drivenparts 45, 46, 47 and 48. The driven part 92 is secured to the shaft 79,whereas the driven part 93 is rotatable on the shaft 79 and is securedto an arm 94 having a notch 96 engaging a pin 97 secured to theeccentric 78, which thus is bodily rotatable with the driven part 93.Each clutch 93 comprises also a driving part 67 which is continuouslyrotated by a corresponding pinion 70 of the sleeve 71.

Each driving part 67 (FIG. 2) may be transversely displaced between twopositions to bring the teeth 76 on the plan of the selected one of theadditional teeth 54 and 56 of the respective driven parts. To this endeach driving part 67 is provided with an annular groove 95 engaged by alug 99 of a lever 100 pivoted on a pin 101 secured to the carriage 20.Another lug 102 of each lever 100 is provided with a notch 103 engaginga corresponding code bar 104 extended along the whole width of themachine and fulcrumed on the stationary frame of the machine by means oftwo end pins 105.

The printing device comprises an additional clutch 106 (FIG. 1) forcontrolling the printing operation of the se- 36, which .thusisbodilyrolected typewheel 12. The clutch 106 is formedof a driven part107 secured to a shaft 108 rotatable on the flanks 21 and 22 of thecarriage 20 and having two additional teeth 109 located on the sameplan. Furthermore, the clutch 106 comprises a driving part 110 slidableon a shaftlll secured to the flanlc 22 and similar to the.driving part67 of-the clutches 43. and 91, with the only dif ferencethat the part110 is provided with a pin-112C0- operating with a frontal cam113secured to the shaft 111 and having two similar lobes. The" clutch106 is started with a delay of 60 degrees with'respect to the clutches43 and 91. The driving part 110 ofthe clutch 106 is provided with agroove163 engaged by a lever 114 fulcrumed on a pin 115 secured to thecarriage'20 and normally held in the position of the figure by a springurged locking member 116. The lever 114 is-provided with a lug 117having a notch 118 engaging another bar 119 similar to the code bars104, the bar 119 being rotated counterclockwise to cause the typecorresponding to the code combination represented by the bars 104 to beprinted. 7

Secured to the shaft 108 is another cam 120'having two similar lobes andcooperating with an arm 122 of a bail 123 secured to a shaft 124 andurged'by a spring 121, the shaft 124 being rotatably. mounted on theflanks 21 and 22. Another arm 125 of the bail- 123, forming the hammerof the printing-device, i adaptedto engage a notch 126 of the plate 14presently facing the printing point for causing the corresponding wheel12 to strike the platen 11. The arm 125 normally enters a notch'127provided on a universal bar 128,-which engages a recess 129 of eachplate 14.

The bar 128 is fulcrumed on the shaft 124 and is normally urged by apair of springs 131 tensioned between a pair of projections 134 and theflanks 21 and 22 to contact the fore edge of the arm 125. This latter isalso provided with a projection 132 engaging a hole 133 of the bar 128.The propections 134 are adapted to cooperate with a pair of shoulders136 provided on the flanks 21 and 22 of the carriage 20. A third arm 137of the bail 123 is adapted to cooperate with another cam 138 having twosimilar lobes and normally secured to the shaft'108. The cam 138 isprovided with three sections having different edges adapted to engagethe arm 137 when the machine is operated at 50, 75 and 100 baudsrespectively. To this end the cam 138 may be axially securedto threedifferent positions so as to cause the appropriate section of the cam138 to engage the arm 137, according to the speed of the machineoperation.

Another arm 139 of the bail 123 is provided with a pr0- jection140--adapted to cooperate with a pin-141. of a lever 142 pivoted on theshaft 124. The lever 142 is normally urged by .a spring 143 to contact apin 144 secured to the flank 21 of the carriage 20. The spring 143 isalso connected to an arm 146 secured to a shaft 147 rotatably mounted onthe flank 21 of the carriage 20. Secured to the shaft 147 is also alever 148, which is variably positionable by hand for adjusting thetension of the spring 143.

Secured to each plate 14 (FIG..4) is a pin 149 pivotally mounting alever 150 provided with a projection 151 normally urged by a spring 152to contact a shaft 153 secured to the flanks 18 and 19. The lever 150 isalso provided. with a wedge shaped projection 154 adapted to cooperatewith an inner pinion 155 integral with each wheel 12 and having a pitchequal to the pitch of the types carried by the wheel 12. 5

Finally, secured to the shaft 108 ('FIG. 1) is a complementary cam 156cooperating with'a lever 157 fulcrumed on the shaft 147. The lever- 157is linked through a-link 158 to a lever 159 fulcrumed on a pivot 160secured'to the flank 21. The lever 159 is provided with aprojection 161adapted to cooperate with a set of four'notches 162 provided on the rearsquare bar 16 at a mutual distance equal to the distance between thewheels 12.

I The printing device operates as follows.

'The code bars 104 (FIGS. 2 and 3) are simultaneously selectivelypositioned according to the code combination of the characterto beprinted in a manner known per se, for example'under the control of thereceived signals of a teleprinter or under the control of a depressedkey. The code bars 104 through the corresponding levers 100, displacethe driving parts 67 of the corresponding clutches 43 and 91, thusselectively rotating 180 degrees the driven parts 45, 46, 47, 48, 92 and93 together with the eccentrics 35, 36, 37 and 38 and respectively 77and 78.

The connecting rod 41 (FIG. 2) is then vertically displaced toselectively rock the bail 32. Then the bar 31 displaces the racks 26vertically and rotates the wheels 12 simultaneously so as to bring thetype to be printed in front of the printing line. Simultaneously theconnecting rod 81 (FIG.'' 3) is displaced vertically and selectivelyrocks the bail 84 so as to bring the wheel 12 carrying the type to beprinted in front of the printing point. The plate 14 carrying this wheel12 is thus located in the longitudinal planeof the notch 127 (FIG. 1) ofthe bar 128 and its notch 126 is engaged by the arm 125.

Simultaneously with the selective positioning of the code bars 104(FIGS. 2 and 3), the bar 119 (FIG. 1) is rocked counterclockwise andthrough the lever 114 displaces the driving part 110 of the clutch 106leftwards, so bringing the teeth 76 thereof on the plan of the teeth 109of the driven part 107. After 60 degrees of rotation of the clutches 43and 91 (FIGS. 2 and 3), the driven part 107 (FIG. 1) of the clutch 106begins to rotate counterclockwise for a 180 degree cycle of the shaft108. Upon 60 degrees of the cycle of the shaft 108 the cam 120 releasesthe arm 122 of the bail 123 which however now bears through the arm 137against the cam 138.

Upon 75 degrees of the cycle of the shaft 108, the cam 156 begins torock the lever 157 clockwise. Then the link 158 rocks the lever 159counterclockwise, whereby the projection 161 engages the notch-162corresponding to the selected wheel 12, thus locking the supports 18,19,, 23 in the reached transverse position with respect to the carriage20. This engagement occurs at about 115 degrees of 'the cycle of theshaft 108, that is upon 175 degreesof the cycle of the selectionclutches 43 and 91 (FIGS. Z'and 3).

In the case the machine operates atthe conventional telegraphic speed of50 bands, the cam 138 is secured to the shaft 108 so as to cause itsrightmost section to cooperate with the arm 137 as shown in FIG. 1. Inthis 'case, upon 80 degrees of the cycle of the shaft 108, th:

cam 138 causes thespring 121 to rock the bail 123 clockwise. The springs131 at first cause the bar 128 to follow thebail 123, whereby the fourplates 14 approach the wheels 12 to the platen 11. Then the bar 128 isarrested .bythe shoulders 136, while the bail 123 is further rocked theplaten 11 by the arm 125 engaging the corresponding plate 14. Now theprojection 151 (FIG. 4) of the lever 150 leaves the shaft 153, wherebythe spring 152 rocks the lever 150 counterclockwise and the projection154 engages the pinion 155 of the selected wheel 12 thus adjusting theangular position of this wheel 12. Thereafter the arm 125 (FIG. 1)through the plate 14 causes this wheel 12 to strike-against the platen11 at 120 degrees of the cycle of the shaft 108. Since the support 18,19, 23 is transversely locked by the lever 159 and the selected wheel 12is angularly locked by the projection 154, the selected type ispri'nted' correctly.

'In the last part of the counterclockwise rotation of the bail 123,the'projection 140 of the arm 139 engages the pin 141 of the lever 142.Then the spring 1430f the lever 142 dec'elerates' the speed of the bail123, whereby the arm 1 25 remains slightly detached from the rear edgeof the notch 126 of the plate 14. Therefore, the last part of theprinting stroke of the wheel 12 is etfected by'inertia and any vibrationof the wheel 12 between the platen 11 and the arm 125 is prevented,whereby the imprinting will not be smudged; By manually rocking thelever148 the tension of the spring 143 is adjusted toalter at-will the impactintensity.

The bail 123, after having caused the wheel 12 to effect an imprint,is'engaged again by the cam through the arm 122, which begins to returnthe bail 123 clockwise, thus restoringforward the plate 14 of thewheel12 which has effected the imprint. At the beginning of this returnstroke the projection 151 (FIG. 4) of'the lever 1'50 engages the shaft153, whereby the projection 154 is disengaged from the pinion 155.Simultaneously the cam 156 (FIG. 1), through the lever 157 and the link158, disengages the projection 161 of the lever 159 from the notch 162.Since the code bars 104 may be positioned already during the cycle ofthe clutches 43 and 91 (FIGS. 2 and 3), and since in the first part ofthe rotation thereof, due to the sinusoidal motion originated by theeccentrics, the connecting rods 41 and 81 substantially are notdisplaced, the next selecting cycle or the clutches 43and 91 may beeffected immediately after the preceding one. In the meanwhile the cam120 (FIG. 1) fully restores the bail 123 clockwise and in the last partof the stroke of the bail 123 the arm restores the bail 128 clockwiseand the plates 14 forwards. After the printing operation the carriage isdisplaced rightward one step in a manner known per se. Near the end ofthe cycle of the shaft 108, the pin 112 engages the frontal cam 113 andis displaced rightwards together with the driven part 110 of the clutch106, whereby the bar 119 is returned to the position of FIG. 1. Howeverthe clutch 106 is disengaged only in the case the bar 119 has no morebeen rocked.

It is intended that modifications, improvements, and addition of partsmay be made to the described printing device, without departing from thescope of the invention as defined by the appended claims.

What is claimed is:

1. A printing device for typewriters, teleprinters, accounting and likemachines, comprising in combination,

at least a typecarrier provided with a plurality of different types,

a motion aggregating mechanism for selectively positioning saidtypecarrier according to a predetermined code combination,

said mechanism comprising a group of eccentrics including an outereccentric and at least one inner eccentric, each one associated with acode unit and adapted to selectively assume one of two diametricallyopposite positions, at least an outer eccentric being rotatably mountedon an inner eccentric of said p,

a group of coaxial similar driven pinions associated with saideccentrics,

a group of coaxial similar driving pinions each one conditionable forrotating a corresponding driven pinion degrees,

and connecting means'for enabling each one of said eccentrics to bebodily rotated by the associated driven pinion.

2. A device according to claim 1, comprising in combinati-on:

a first common shaft for mounting said driven pinions,

and a second common shaft parallel to said first shaft for mounting saiddriving pinions.

3. A device according to claim 2, wherein said first common shaft issecured to one of said eccentrics and to the associated driven pinion.

4. A device according to claim 3, wherein said connecting means betweenthe other eccentrics and the other driven pinions comprise incombination: 7

a pin secured to each one of said other eccentrics,

. a member. secured .to each one of said other driven pinions,

and a slot on said member entered by the pin of the associated eccentricto allow-a radial displacement of each outer eccentric with respect tothe associated driven pinion when an inner eccentric is rotated.

5. A device according to claim 3, wherein said connect: ing meansbetween the other eccentrics and the'other driven pinions comprise incombination:

an elementsecured to each one of said other eccentrics,

and a counterelement secured to each one of said other driven pinions,saidelement and said counterelement having a sliding relationship toallow a radial displacement of each outer eccentric with respect to theassociated driven pinion when an inner eccentric is rotated.

6. A device according to claim 5, comprising in combination:

a pair of diametrically opposite portions deprived of teeth oneach.driven pinion, one of said portion normally facing the associateddriving pinion,

a pair of additional teeth angularly aligned with each one of saidportions, said additional teeth being axially mutually offset andbeingbodily rotatable with a corresponding driven pinion,

a further tooth bodily rotatable with each one of sai driving pinions,and normally aligned with the additional teeth not facing thecorresponding driving pinion,

and means for axially aligning one of said additional teeth with saidfurther tooth for preliminarily rotating the associated driven pinion,said further tooth of the various driving pinions being angularlymutually aligned so as to drive said driven pinions synchronously.

7. A printing device for typewriters, teleprinters, ac-

counting and like machines, comprising in combination,

a set of adjacent typewheels each one provided with a plurality ofdifferent types,

a support rotatably mounting said typewheels,

a first motion aggregating mechanism for selectively bodily rotatingsaid typewheels,

a second motion aggregating mechanism for selectively moving saidsupport so as to displace said typewheels axially, each one of said.mechanisms comprising an associated group of eccentrics including anouter eccentric and at least one inner eccentric adapted to assume oneof two diametrically opposite positions according to a predeterminedcode combination, at least an outer eccentric of each group beingrotatably mounted on an inner eccentric of the same group,

a group of-coaxial similar driven pinions associated with each group ofeccentrics,

a group of coaxial similar driving pinions associated with each group ofeccentrics and each one conditionable for rotating a correspondingdriven pinion 180 degrees,

and connecting means for enabling each one of said eccentrics to bebodily rotated by the associated driven pinion.

8. A device according to claim 7, wherein said typewheels are rotated bya first group of eccentrics having an eccentricity variable according tothe powers of two, the smallest eccentric of said first group beingintegral with the. shaft of said driven parts, the other eccentrics ofsaid first group being each one rotatable on the eccentric having thenext lower eccentricity.

9. A device according to claim 8, wherein said support is displaced by asecond group of eccentrics having an eccentricity variable according tothe powers of two, and mounted in manner similar to that of theeccentrics of said first group.

10. A device according to claim 7, comprising in combination:

a stationary paper platen,

a carriage transverselyrmovable step by step with. re-

spect to said platen, means movably mounting said support on saidcarriage, and means for mounting said eccentrics, said driven pinionsand said drivingpinions on said carriage.

11. A device according to claim-10, wherein said type- Wheelsarefulcrumed on individual-pivots. parallelto the printing line, said.pivots being movable to enable thecorresponding'typewheel'to:strike onsaid'platen, -comprising in combination:

a shaft cyclically rotatable at the end of the rotation of said drivenpinions, i and a hammerfacingthe printing point and operable by saidshaft to cause the typewheel located in front of said printing point tobe so moved.

12. A device according to claim 11, comprising in combination: l

a locking member operable for locking said support in the reachedtransverse position,

and means on said shaft for operating said locking member beforeoperation of said hammer.

13. A printing device for typewriters, teleprinters, accounting and likemachines, having a platen, a set of adjacent typewheels fulcrumed onindividual pivots parallel to the printing line, said pivots beingmovable to enable the corresponding typewheel to strike on said platen,a transversely movable common support for said typewheels, a selectingdevice for selectively rotating said typewheels and for selectivelymoving said support, and comprising in combination:

a cyclically rotatable shaft,

a first cam on said shaft,

a second cam on said shaft,

and a hammer facing toward the platen at the location of the printingpoint and controlled, during cyclic rotation of said shaft, first bysaid first cam to effect movement of the typewheel partially toward theplaten and controlled, during the same cyclic rotation of said shaft, bythe second cam thereafter to effect further movement of said typewheeltoward the platen at a predetermined speed condition.

14. A device according to claim 13, comprising further, detent notchesassociated with said typewheels to define type-selective positionsthereof,

latches individual to said wheels normally clear of said 40 detentnotches and movable to engage them,

and means controlled by said cyclically rotatable shaft to engage saidlatches before each printing contact of a typewheel is effected. 15. Adevice according to claim 13, and wherein said cyclically rotatableshaft is rotatable at a number of predeterminable speeds, comprisingtherewith in combination: a plurality of different cam edges on saidsecond cam adapted to be predeterminedly selected for individualcooperation with said hammer,

do said cam edges relatively to each other adapted to predetermine saidfurther printing movement of said type wheel toward said platen atspeeds suited to the selected speed of the cyclically rotatable shaft.

16. A device according to claim 13, comprising therewith in combination:

a decelerating member engageable for displacement from a normal positionthrough the operation of said hammer late in its operating stroke,

spring means urging said decelerating member to its normal position, i

and manually sett able means to adjust the tension of said spring means,thereby to alter the decelerating effect of said decelerating member onsaid hammer.

17. A printing device for typewriters, teleprinters, ac-

counting and like machines, comprising in combination:

a platen,

a set of typewheels axially adjacent to each other parallel of theplaten and normally removed'therefrom transversely of the platen,

a movable support carrying said typewheels for movement parallel to theplaten to align difierent wheels with a printing point on the platen,

mounting plates for said typewheels on said common support situated inadjacent planes transversely of the platen,

means guiding said mounting plates for movement on said support in theirindividual planes to effect imprints by said typewheels,

a selecting device for selectively rotating said type- Wheels and alsofor selectively moving said support parallel to the platen to alignselectively said typewheels with the printing point,

a notch in each of said mounting plates,

a hammer for operating said mounting plates transversely to said platenand having an operating end adapted to be straddled by the notch of anyof said mounting plates if brought into registration therewithlengthwise of the carriage by said selecting device,

a universal member extending parallel to the platen and along with theoperating end of said hammer also adapted to be straddled by saidnotches,

a recess in said universal member being transversely of the platen inalignment with the printing point, wherefor any mounting plate isoperable by said hammer if brought into operative alignment therewith,

a first cam to cause a partial operation of said hammer and thereby todrive partially toward the printing position whichever mounting plate isaligned with the printing point and further also to cause an operationof said universal member to drive the other mounting plates alsopartially toward printing position,

and a second cam to cause a further operation of said hammer which willdrive only that mounting plate further toward printing position which isin alignment therewith, thereby to cause an imprint by a type of thattypewheel.

References Cited UNITED STATES PATENTS ROBERT -E. PULFREY, PrimaryExaminer.

E. S. BURR, Assistant Examiner.

